The Colorado Department of Public Health and Environment has issued the following
What: Ozone Action Day Alert.
Where: Douglas, Jefferson, Denver, western Arapahoe, western Adams, Broomfield, Boulder, Larimer, and Weld Countie
S When: 400 PM Sunday July 06 to 400 PM Monday July 07
Impacts: Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Showers and thunderstorms are expected to limit ozone concentrations on Sunday. On Monday, ozone may reach levels that are Unhealthy for Sensitive Groups in the northern portions of the Front Range including Denver, Fort Collins, and Greeley. For Colorado air quality conditions, forecasts, and advisories, visit: https://www.colorado.gov/airquality/colorado_summary.aspx If possible, please help us reduce ozone pollution by limiting driving gas and diesel-powered vehicles until at least 4 p.m. Monday, July 7, 2025. Colorado is also addressing ozone pollution through state policies. For more information about health impacts and how ozone pollution forms in Colorado, visit: https://cdphe.colorado.gov/ozone- pollution-and-your-health
Health Information: Increasing likelihood of respiratory symptoms and breathing discomfort in active children and adults and people with lung disease, such as asthma. Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy outdoor exertion.